This invention relates generally to the heating and cooling of liquids, and more particularly, to the improvements in a compression-type refrigeration system for heating and cooling liquids such as water in a swimming pool.
In the past, many systems have been employed to heat water which utilize resistive-type electric heating elements, or relied upon the combustion of either natural gas or fossil fuel. The former system is well-known to be highly inefficient; the latter system, in addition to also being inefficient, includes the short-comings attendant to combustion, i.e., exhaust gases, a needed source of fuel, high temperature water conduit corrosion, and operational hazards.
A more recent development is disclosed in U.S. Pat. No. 3,513,663, of which applicant was co-inventor. In its broadest sense, this invention teaches te use of conventional refrigeration components, with modification, to heat a first liquid source, e.g., a swimming pool, while simultaneously cooling a second liquid source, e.g., a ground well. Preferably coaxial conduit is utilized in the construction of condenser and evaporator coils for the purpose of achieving opposing, segregated, heat exchange flow between refrigerant and liquid. In operation, when one liquid source is passed through the condenser coil while the second liquid source is passed through the evaporator coil, coaxial, opposing, segregated refrigerant liquid flow in seriatum through the coils will result in efficient heating of the first liquid, while cooling the second liquid. Sensor control and liquid pumping means are also disclosed therein.
The present invention contemplates improvements over the above-disclosed U.S. Patent. One aspect of these improvements includes the elimination of the second or ground liquid source. Another aspect of these improvements comprises liquid and/or refrigerant flow reversal or rerouting to conveniently heat or cool one liquid source. And finally, this invention discloses select use of external fluid flow over condenser or evaporator coils to enhance the coefficient of performance.